Electrical connectors of the type for mass termination to flat multiconductor ribbon cable have been in use particularly in the data communications industry for some time. Such mass termination electrical connectors typically include insulation displacement contacts (IDC) by which conductors contained in a flat multiconductor ribbon cable are commonly terminated without need for stripping the conductors from the insulation. One example of such a connector is U.S. Pat. No. 3,990,767 (Narozny), wherein all the contacts are formed initially to have an identical configuration for manufacturing purposes and which are later bent during assembly to achieve a pitch transition. In the Narzony connector, electrical interconnection is made from a flat multiconductor cable wherein conductors are spaced at 0.050 inch to a standard D-face configuration wherein the pins or sockets are located at 0.0545 inch.
Demands in the communications industry have been placed upon the electrical connector manufacturers for adding protection against electromagnetic and radio frequency interference (EMI/RFI), smaller sizes in an effort to conform to higher density packaging and lower manufacturing costs. One example of an electrical connector having insulation displacement contacts, as well as a metal shell for electrical protection is U.S. Pat. No. 4,470,655 Kalka, et al.). As in the Narozny patent, the Kalka, et al. device achieves pitch transition by the use of identical contact elements having a central deformable strap portion that is bent to achieve the desired pitch transition. In another example of an electrical connector of the IDC type, albeit without a metal shell, U.S. Pat. No. 4,241,970 (Rider, Jr., et al.) discloses an electrical connector having IDC contacts that are formed during manufacture to have the desired pitch transition which is stated to result in a design with a lower profile and economy of manufacture.
In keeping with the trend in the communications industry, it is desirable to provide an electrical connector having IDC's for mass termination and which includes a metal shell for electrical protection and is constructed considering the overall size limitations needed by the industry.